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Finding the Fourth Proportional to 163.56, 245.40 and 139.80

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Solution

The fourth proportional to 163.56, 245.40 and 139.80 is: 209.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    163.56 : 245.40 = 139.80 : x
  2. Step 2: Convert to fraction form
    163.56/245.40 = 139.80/x
  3. Step 3: Cross multiply
    163.56x = 245.40 × 139.80
  4. Step 4: Simplify right side
    163.56x = 34,306.92
  5. Step 5: Solve for x
    x = 34,306.92/163.56
  6. Step 6: Final answer
    x = 209.75

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.